Many recent researchers have ventured a physical modelling of mean areal precipitation with a view to ensuring an appropriate analysis of climate change. Preliminary results of a simple, practical and dynamic integration method of incomplete daily precipitation data for a mountainous catchment are presented here. This is a combinatorial technique of the Thiessen method and precipitation gauge availability. The estimated catchment precipitation is corrected for elevation variations. This double technique preserves, to a large extent, the physical structure of precipitation information which is vital for climate change interpretation. Furthermore, the proposed method can handle successfully any change in the gauge network, the greatest limitation of the inflexible Thiessen method.